Problem: Simplify the following expression: ${-3(6a+12)-(2+a)}$
Answer: Distribute the ${-3}$ into the first set of parentheses: $ {-3(}\gray{6a+12}{)} - (2+a) $ $ {-18a-36} - (2+a) $ The minus sign in front of the parentheses means we multiply each term inside the parentheses by ${-1}$ $ -18a-36 {-1(}\gray{2+a}{)} $ $ -18a-36 {-2-a} $ Rewrite the expression to group the ${a}$ terms and numeric terms: $ {-18a - a} {-36 - 2}$ Combine the ${a}$ terms: $ {-19a} {-36 - 2}$ Combine the numeric terms: $ {-19a} {-38}$ The simplified expression is $-19a-38$